>>9773191 TYB nice and meaty flesh nice bakes

Should We All Be Wearing Face Masks? Here's Why Experts Are So Conflicted

Nicely written article even has pictures…kek

We have reviewed the results of more than a dozen randomised trials of face masks and transmission of respiratory illnesses. We found the current best evidence suggests wearing a mask to avoid viral respiratory infections such as COVID-19 offers minimal protection, if any.

Conflicting recommendations

Two of the world's major health organisations disagree on mask wearing. The World Health Organisation (WHO) currently discourages mask use:

There is currently no evidence that wearing a mask (whether medical or other types) by healthy persons in the wider community setting, including universal community masking, can prevent them from infection with respiratory viruses, including COVID-19.

WHO does recommend special masks (N95 masks or equivalent) plus other protection for health-care workers working with people who have, or are suspected to have, COVID-19.

By contrast, the Centres for Disease Control and Prevention (CDC) in the United States has recently recommended everyone wear a (cloth) mask. However, this is to prevent infected people passing on the infection, not to prevent the wearer getting infected.

Who is right? Does wearing a mask protect the wearer? Does it protect others?

Current best evidence

To resolve this question, we analysed 14 randomised trials of mask wearing and infection for influenza-like illnesses. (There are no randomised trials involving COVID-19 itself, so the best we can do is look at similar diseases.)

When we combined the results of these trials that studied the effect of masks versus no masks in health-care workers and the general population, they did not show that wearing masks leads to any substantial reduction of influenza-like illness. However, the studies were too small to rule out a minor effect for masks.

Why don't masks protect the wearer?

There are several possible reasons why masks don't offer significant protection. First, masks may not do much without eye protection. We know from animal and laboratory experiments that influenza or other coronaviruses can enter the eyes and travel to the nose and into the respiratory system.

While standard and special masks provide incomplete protection, special masks combined with goggles appear to provide complete protection in laboratory experiments. However, there are no studies in real-world situations measuring the results of combined mask and eyewear.

The apparent minimal impact of wearing masks might also be because people didn't use them properly. For example, one study found less than half of the participants wore them "most of the time". People may also wear masks inappropriately, or touch a contaminated part of the mask when removing it and transfer the virus to their hand, then their eyes and thus to the nose.

Masks may also provide afalse sense of security, meaning wearers might do riskier things such as going into crowded spaces and places.

Do masks protect others?

Could masks protect others from the virus that might have been spread by the mask wearer? A recent Hong Kong laboratory study found some evidence masks may prevent the spread of viruses from the wearer.

They took people with influenza-like symptoms, gave half of them masks and half no masks, and for 30 minutes collected viruses from the air they breathed out, including coughs.

Masks did reduce the amounts of droplets and aerosols containing detectable amounts of virus. But only 17 of the 111 subjects had a coronavirus, and these were not the SARS-CoV-2 coronavirus. While the study is promising, it needs to be repeated urgently.

We also don't know how this reduction of aerosols and droplets translates to reduction of infections in the real world. If there is an effect, it may be diluted by several factors such as ill people who don't wear a mask and "well" people who have no symptoms but are still carrying and spreading the virus.

Masks for some?

If wearing masks does substantially reduce the spread of the infection to others, what should we do? We could ask everyone with any respiratory symptoms to wear masks in public. That could supplement other strategies such as social distancing, testing, tracking and tracing to reduce transmission. This article is republished from The Conversation under a Creative Commons license.

https://www.sciencealert.com/this-is-why-advice-on-whether-you-should-wear-a-mask-is-just-so-confusing